Australian Gmelina Plant Care

Australian Gmelina (Gmelina australis) belongs to the Lamiaceae family within the Gmelina genus.

Australian Gmelina displays a fast-growing, upright shrub growth habit, reaching up to 6 ft tall with a spread of approximately 4 ft. Australian Gmelina produces showy clusters of tubular yellow flowers.

Leaf size: approximately 4 inches.

Water a young or newly planted Australian Gmelina every 7–10 days, soaking the whole root zone, until it is established — usually one to two growing seasons. Established trees mainly need water during long dry spells. In a container, water whenever the top few centimetres of soil are dry.

Australian Gmelina thrives in full sun to partial shade.

Gmelina australis tolerates temperatures of 65–85°F. Australian Gmelina prefers humidity levels of 40–70%.

Well-draining loamy soil with added compost for nutrients. Good drainage is essential for Australian Gmelina to prevent waterlogging, which leads to root rot and fungal issues.

Feed Australian Gmelina every 6 months during the growing season with a balanced, slow-release fertilizer at the rate on the label. Established trees in good soil often need little extra feeding, so let weak growth or pale foliage guide you.

Stop feeding by late summer so new growth can harden before winter.

The PlantoScan app can remind you when to water and when to fertilize each plant.

Choose a spot with full sun to partial shade and well-draining loamy soil with added compost for nutrients. Avoid low spots where water collects after rain.

Australian Gmelina is suited to USDA Zone 13b.

Plant container-grown or balled-and-burlapped trees in spring or early autumn, setting the root flare at soil level, and water well after planting.

Australian Gmelina can spread to about 4 ft (1.2 m) and reach about 6 ft (2 m) tall. Space plants about 4 ft (1.2 m) apart so mature crowns don't crowd each other, and plant at least half that distance from buildings, fences and paths.

Planning a row or hedge? Try the tree spacing calculator.

Prune Australian Gmelina while it is dormant in late winter: first remove dead, damaged and crossing branches, then thin lightly for shape.

If it flowers in spring, prune right after flowering instead so you don't remove next year's buds. Never take off more than about a quarter of the tree in one year.

Australian Gmelina is frost-tender (hardy to USDA zone 13). In colder areas grow it in a container and move it to a bright, frost-free place before the first frost.

Australian Gmelina can be propagated through seeds, softwood cuttings. Similar propagation techniques also apply to gmelina plant care, which shares the same genus.

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Australian Gmelina is susceptible to aphids, spider mites, whiteflies. Inspect the foliage regularly, especially along leaf undersides and stems. Treat infestations promptly with insecticidal soap or neem oil to prevent spread.

Yellow leaves, brown tips or drooping? See common plant problems and how to fix them.

Australian Gmelina grows outdoors in USDA Zone 13b. It survives winters down to planting zone 13b. In cooler regions, grow Australian Gmelina as a houseplant or bring it indoors before the first frost.